From patchwork Wed Mar 10 18:19:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Gladkov X-Patchwork-Id: 12128985 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.7 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 417CAC432C3 for ; Wed, 10 Mar 2021 18:21:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1141964FBA for ; Wed, 10 Mar 2021 18:21:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233569AbhCJSUq (ORCPT ); Wed, 10 Mar 2021 13:20:46 -0500 Received: from raptor.unsafe.ru ([5.9.43.93]:56466 "EHLO raptor.unsafe.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232790AbhCJSUU (ORCPT ); Wed, 10 Mar 2021 13:20:20 -0500 Received: from comp-core-i7-2640m-0182e6.redhat.com (ip-94-113-225-162.net.upcbroadband.cz [94.113.225.162]) by raptor.unsafe.ru (Postfix) with ESMTPSA id 677E940CE4; Wed, 10 Mar 2021 18:20:16 +0000 (UTC) From: Alexey Gladkov To: LKML , "Eric W . Biederman" Cc: Alexey Gladkov , Alexander Viro , Kees Cook , Linux Containers , Linux FS Devel Subject: [PATCH v5 0/5] proc: Relax check of mount visibility Date: Wed, 10 Mar 2021 19:19:55 +0100 Message-Id: X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.6.4 (raptor.unsafe.ru [0.0.0.0]); Wed, 10 Mar 2021 18:20:19 +0000 (UTC) Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org If only the dynamic part of procfs is mounted (subset=pid), then there is no need to check if procfs is fully visible to the user in the new user namespace. Changelog --------- v4: * Set SB_I_DYNAMIC only if pidonly is set. * Add an error message if subset=pid is canceled during remount. v3: * Add 'const' to struct cred *mounter_cred (fix kernel test robot warning). v2: * cache the mounters credentials and make access to the net directories contingent of the permissions of the mounter of procfs. --- Alexey Gladkov (5): docs: proc: add documentation about mount restrictions proc: Show /proc/self/net only for CAP_NET_ADMIN proc: Disable cancellation of subset=pid option proc: Relax check of mount visibility docs: proc: add documentation about relaxing visibility restrictions Documentation/filesystems/proc.rst | 18 ++++++++++++++++++ fs/namespace.c | 27 ++++++++++++++++----------- fs/proc/proc_net.c | 8 ++++++++ fs/proc/root.c | 25 +++++++++++++++++++------ include/linux/fs.h | 1 + include/linux/proc_fs.h | 1 + 6 files changed, 63 insertions(+), 17 deletions(-)